Excel Localizations Generator #

Generate type-safe Flutter/Dart localizations from Excel files with automatic language validation and modern Dart conventions.

Features #

• 📊 Multi-sheet Excel support - Organize translations by feature/category
• 🎯 Type-safe generated code - Compile-time safety with auto-completion
• 🔤 String interpolation - Dynamic values using {variable} syntax
• 🌍 184+ language codes - Full ISO 639-1 support with country variants
• 🐪 CamelCase methods - Modern naming (app_title → appTitle)
• ✅ Automatic validation - Validates language codes with helpful error messages
• 🚀 Zero-config CLI - Works with pubspec.yaml configuration

Installation #

dependencies:
  excel_translator:
    git: https://github.com/your/repo.git

Quick Start #

1. Create Excel File #

Create an Excel file with language codes in the header row:

2. Configure (Optional) #

Add to pubspec.yaml:

excel_translator:
  excel_file: assets/localizations.xlsx
  output_directory: lib/generated
  class_name: AppLocalizations

3. Generate #

# Simple - uses pubspec.yaml config
dart run excel_translator

# Or specify parameters
dart run excel_translator assets/localizations.xlsx lib/generated

4. Use Generated Code #

Traditional Usage (with BuildContext)

import 'lib/generated/generated_localizations.dart';

// In Flutter widgets
Widget build(BuildContext context) {
  return Text(AppLocalizations.of(context).sheet.hello);
}

// Access specific language
final loc = AppLocalizations.english;
print(loc.sheet.hello);           // "Hello"
print(loc.sheet.appTitle);        // "My App" (camelCase from app_title)

// String interpolation
print(loc.sheet.welcomeMessage(name: "John")); // "Welcome John!"

Global Instance Usage (without BuildContext)

For repositories, services, or any non-UI code that needs translations:

import 'lib/generated/generated_localizations.dart';

// Simple current language detection (no initialization needed)
class UserRepository {
  void validateUser() {
    final errorMsg = AppLocalizations.current.sheet.invalidUser;
    throw Exception(errorMsg);
  }
}

// Or with explicit initialization in main.dart
void main() {
  // Option 1: Auto-detect system language
  AppLocalizations.initializeGlobal();
  
  // Option 2: Set specific language
  AppLocalizations.initializeGlobalWithLanguage('en');
  
  // Option 3: Initialize from context (in widget)
  AppLocalizations.initializeGlobalFromContext(context);
  
  runApp(MyApp());
}

// Use global instance anywhere without context
class OrderService {
  void processOrder() {
    final successMsg = AppLocalizations.instance.sheet.orderSuccess;
    print(successMsg);
  }
}

// Runtime language switching
AppLocalizations.updateGlobalLanguage('id'); // Switch to Indonesian

Flutter App Setup

MaterialApp(
  localizationsDelegates: const [
    ...AppLocalizations.delegates,
  ],
  supportedLocales: AppLocalizations.supportedLanguages
      .map((language) => Locale(language))
      .toList(),
  // ...
)

Excel File Format #

Single Sheet Example #

Multi-Sheet Example #

Sheet "login":

Sheet "buttons":

Generates:

final loc = AppLocalizations.english;
print(loc.login.title);           // "Login"
print(loc.login.forgotPassword);  // "Forgot Password?" (camelCase)
print(loc.buttons.submit);        // "Submit"

Global Instance Benefits #

The global instance feature allows you to access translations anywhere in your app without requiring a BuildContext. This is particularly useful for:

Use Cases #

• Repository Layer: Access error messages in data repositories
• Service Classes: Localize API error responses or validation messages
• Business Logic: Add localized messages in use cases or domain services
• Background Tasks: Use translations in isolates or background processes
• Utility Functions: Helper functions that need localized strings

Key Features #

• Two Access Patterns:
  • AppLocalizations.current - Simple, no initialization required
  • AppLocalizations.instance - Global singleton with initialization control
• System Language Detection: Automatically detects device language
• Runtime Language Switching: Change language without rebuilding widgets
• Fallback Support: Falls back to default language if requested language not available
• Thread Safe: Safe to use in isolates and background tasks
• No Context Required: Access translations in any Dart class

Example: Repository with Localized Errors #

class AuthRepository {
  Future<User> login(String email, String password) async {
    try {
      // API call
      return await api.login(email, password);
    } catch (e) {
      // Option 1: Simple current language detection (no setup required)
      throw Exception(AppLocalizations.current.errors.loginFailed);
      
      // Option 2: Using global instance (requires initialization)
      // throw Exception(AppLocalizations.instance.errors.loginFailed);
    }
  }
}

Language Support #

Supports 184+ ISO 639-1 language codes including:

• Basic codes: en, id, es, fr, de, ja, ko, zh
• Locale formats: en_US, pt_BR, zh_CN, en-US
• Comprehensive validation with helpful error messages

CLI Options #

# Zero-config (uses pubspec.yaml)
dart run excel_translator

# Full command
dart run excel_translator [excel_file] [output_dir] [options]

Options:
  -c, --class-name=<name>     Generated class name (default: AppLocalizations)
  -d, --delegates             Include Flutter delegates (default: true)
  -h, --help                  Show help

Generated Code Structure #

lib/generated/
├── generated_localizations.dart     # Main class with delegates
├── build_context_extension.dart     # context.loc extension
├── sheet1_localizations.dart        # Sheet-specific classes
└── sheet2_localizations.dart        # ...

Requirements #

• Dart SDK 2.17+
• Flutter 3.0+ (for Flutter projects)
• Excel files in .xlsx format

License #

MIT License